Serializer ASIC Research Articles

A 5-Gbps serializer ASIC in 130 nm for high-speed front-end readout applications

This paper presents the design and the test results of a low-power 5 Gbps 10:1 serializer chip with the self-check function based on a standard 130 nm CMOS technology. This serializer chip adopts a multi-level design scheme with a combination of the multi-phase structure (5:1 module) in the low data rate part and the tree structure (2:1 module) in the high date rate part. The high data rate 2:1 module adopts a latch-induced latency control circuit to ensure the timing margin across corners. The serializer chip has been fully tested, wide-open 5 Gbps output eye diagram has been captured, and the logic function has also been verified. The measured power consumption of the whole chip is 42 mW including Rx/Tx, and the power consumption of the serializer core is around 12.1 mW.

Mass production of a trigger data serializer ASIC for the upgrade of the muon spectrometer at the ATLAS experiment

The Trigger Data Serializer (TDS) is a custom ASIC designed for the upgrade of the innermost station of the endcap ATLAS Muon Spectrometer. It is a mixed-signal chip with two working modes that can handle up to 128 detector channels. A total of 6,000 TDS ASICs have been produced for detector operation. This paper discusses a custom automatic test platform we developed to provide quality control of the TDS ASICs. We introduce the design, test procedures, and results obtained from this TDS testing platform.

LOCx2-130, a low-power, low-latency, 2 × 4.8-Gbps serializer ASIC for detector front-end readout

In this paper, we present the design and test results of LOCx2-130, a low-power, low-latency, dual-channel transmitter ASIC for detector front-end readout. LOCx2-130 has two channels of encoders and serializers, and each channel operates at 4.8 Gbps. LOCx2-130 can interface with three types of ADCs, an ASIC ADC and two COTS ADCs. LOCx2-130 is fabricated in a commercial 130-nm CMOS technology and is packaged in a 100-pin QFN package. LOCx2-130 consumes 440 mW and achieves a latency of less than 40.7 ns.

Design of a Trigger Data Serializer ASIC for the Upgrade of the ATLAS Forward Muon Spectrometer

The small-strip Thin Gap Chamber (sTGC) will be used for both triggering and precision tracking purposes in the upgrade of the ATLAS forward muon spectrometer. Both sTGC pad and strip detectors are readout by a Trigger Data Serializer (TDS) ASIC in the trigger path. This ASIC has two operation modes to prepare trigger data from pad and strip detectors respectively. The pad mode (pad-TDS) collects the firing status for up to 104 pads from one detector layer and transmits the data at 4.8 Gbps to the pad trigger extractor every 25 ns. The pad trigger extractor collects pad-TDS data from eight detector layers and defines a region of interest along the path of a muon candidate. In the strip mode (strip-TDS), the deposited charges from up to 128 strips are buffered, time-stamped, and a trigger matching procedure is performed to read out strips underneath the region of interest. The strip-TDS output is also transmitted at 4.8 Gbps to the following FPGA processing circuits. Details about the ASIC design and test results are presented in this paper.

A low-power, low-latency, dual-channel serializer ASIC for detector front-end readout

In this paper, we present a dual-channel serializer ASIC, LOCx2, and its pin-compatible backup, LOCx2-130, for detector front-end readout. LOCx2 is fabricated in a 0.25-μm Silicon-on-Sapphire CMOS process and each channel operates at 5.12 Gbps, while LOCx2-130 is fabricated in a 130-nm bulk CMOS process and each channel operates at 4.8 Gbps. The power consumption and the transmission latency are 900 mW and 27 ns for LOCx2 and the corresponding simulation result of LOCx2-130 are 386 mW and 38 ns, respectively.

Characterization of a Serializer ASIC Chip for the Upgrade of the ATLAS Muon Detector

We report on the design of a serializer ASIC to be used in the ATLAS forward muon detector for trigger data transmission. We discuss the performance of a prototype chip covering power dissipation, latency and stable operating line rate. Tests show that the serializer is capable of running at least at 5.76 Gbps with a bit error ratio below 1x10^{-15}, and a power consumption of 200 mW running at 4.8 Gbps. The latency between the start of loading 30 bits into the serializer to the transmission of the first bit from the serializer is measured to be about 6 ns.

FPGA Implementation of a Fixed Latency Scheme in a Signal Packet Router for the Upgrade of ATLAS Forward Muon Trigger Electronics

We propose a new fixed latency scheme for Xilinx gigabit transceivers that will be used in the upgrade of the ATLAS forward muon spectrometer at the Large Hadron Collider. The fixed latency scheme is implemented in a 4.8 Gbps link between a frontend data serializer ASIC and a packet router. To achieve fixed latency, we use IO delay and dedicated carry in resources in a Xilinx FPGA, while minimally relying on the embedded features of the FPGA transceivers. The scheme is protocol independent and can be adapted to FPGA from other vendors with similar resources. This paper presents a detailed implementation of the fixed latency scheme, as well as simulations of the real environment in the ATLAS forward muon region.

Component Prototypes Towards a Low-Latency, Small-Form-Factor Optical Link for the ATLAS Liquid Argon Calorimeter Phase-I Trigger Upgrade

This paper presents several component prototypes towards a low-latency, small-form-factor optical link designed for the ATLAS Liquid Argon Calorimeter Phase-I trigger upgrade. A prototype of the custom-made dual-channel optical transmitter module, the Miniature optical Transmitter (MTx), with separate transmitter optical sub-assemblies (TOSAs) has been demonstrated at data rates up to 8 Gbps per channel. A Vertical-Cavity Surface-Emitting Laser (VCSEL) driver ASIC has been developed and is used in the current MTx prototypes. A serializer ASIC prototype, operating at up to 8 Gbps per channel, has been designed and tested. A low-latency, low-overhead encoder ASIC prototype has been designed and tested. The latency of the whole link, including the transmitter latency and the receiver latency but not the latency of the fiber, is estimated to be less than 57.9 ns. The size of the MTx is 45 mm x 15 mm x 6 mm.

A 5.28-Gb/s serializer ASIC for uncompressed long-haul multimedia interconnects

We report a 5.28-Gb/s serializer ASIC for uncompressed long-haul video interconnects. Our ASIC is based on the serializer architecture which maintains the constant output data rate for various resolutions of incoming video signals from VGA to UXGA. With this, a wide-band phase-locked-loop in a serializer and a continuous-rate clock-and-data-recovery circuit in a de-serializer are not necessary. The serializer ASIC contains clock-and-data-recovery circuits, de-multiplexers, a digital processing block, a phase-locked-loop, multiplexers. A VCSEL driver circuit is also integrated so that it can be used for long-haul transmission with multimode fiber. The ASIC produces 5.28-Gb/s serialized driving currents for VCSEL from parallel input signals. It occupies 3.45 mm2 and consumes 151.7 mW.

A 16:1 serializer ASIC for data transmission at 5 Gbps

A high speed, low power 16:1 serializer has been developed with a commercial 0.25 μm silicon-on-sapphire CMOS technology. The serializer operates from 4.0 to 5.7 Gbps. The total jitter is 62 ps and the eye opening of the bathtub curve is 122 ps at bit error rate of 10−12 at 5 Gbps. Power consumption is 463 mW at 5 Gbps. A proton beam test indicates the serializer is suitable for applications in high energy physics experiments.